In certain fiber optical components and applications using small packages, it is necessary to form a miniature bend in the bare fiber to change the direction of the fiber. To avoid light loss and maintain a useful longevity in an unprocessed bent fiber, the turn typically requires a bend radius of 2 cm or more. This radius may be substantially reduced to as little as 50.mu. using a miniature bend. To form a miniature bend, the diameter along a length of bare fiber is reduced to as little as 1 .mu. or less, by, for example, drawing, etching, or a combination thereof. In the reduced diameter region, the fiber conducts light by internal reflection at least partially due to the difference in index of refraction at the interface between the fiber and the surrounding environment, generally air. Thus, in this region, the fiber may be bent with no substantial light loss from the bend. See U.S. Pat. Nos. 5,138,676 and 5,452,383, the disclosures of which are incorporated by reference herein.
In such miniature bends, it is desirable in some applications to keep the radius of curvature in the bend region to a value of 0.5 mm or larger to avoid loss of optical energy in the bend region. Because the bend is symmetrical, the bend region of the fiber protrudes above the plane of the fiber, as can be seen in FIG. 1. If the fiber lies close to a surface, the bend may potentially contact the surface. Generally, contact of the fiber in the bend region with any surface also causes light loss, which is undesirable. Therefore, the input fibers to a symmetric miniature bend must be spaced a sufficient distance from such a surface to prevent contact between the surface and the bare fiber of the bend. Alternatively, the surface must be formed with a deviation to avoid contact with the bend.